There are many situations where a need arises to move a “load” along a columnar structure. For example, various maintenance and construction operations require workpieces to be raised up poles or ladders (e.g., mounting cameras on poles, changing lightbulbs in cathedral ceiling environments, attaching wireless communication equipment on towers, etc.). Utility workers themselves often need to climb poles to perform installation and repair work at elevated locations. Recreational activities may also require the need to move people or equipment into raised locations along a columnar structure (e.g., raising a deer stand into location in a tree).
The art is replete with various arrangements for performing these functions. These arrangements may require a large number of moving parts, or are not particularly well-suited for a variety of different purposes; that is, each individual situation has tended to develop its own, unique arrangement for moving loads along specific types of columnar structures.
Prior art arrangements that are designed for use with irregularly-shaped columnar structures (for example, trees) are configured to concentrate a load force upon a minimal number of points of contact. As a result, the traction associated with the arrangement is limited and may result in damaging the tree or other such structure.
Various prior art systems require the inclusion of some type of “brake”, or used ground-attached booms. In either event, if the arrangement for stopping fails, the results may be catastrophic.
The arrangements used in an urban environment (such as, for example, to raising wireless equipment up a telephone pole) use separate support systems and require a large operating footprint (including a utility truck, for example), often resulting in street traffic being shut down in an area surrounding the work location.
Moreover, many prior art arrangements are very complex configurations, with a large number of separate components, thus resulting in expensive solutions that are often very heavy and may provide more opportunities for catastrophic failure.